Sack Lunch Seminar (SLS)

Abstract:
There are remarkable trends in atmospheric and ocean circulation in West Antarctica that have been implicated as causal agents for the retreat of the great ice shelves in West Antarctic (most notably, the Pine Island Glacier). Similarly, the remarkable warming in NE Canada and Greenland over the past two decades are also associated with trends in atmospheric circulation. In this presentation, I will present observational and modeling evidence that suggests all of these recent high latitude trends are a results of teleconnections from the tropical Pacific. Two obvious hypotheses for the trends in the tropical Pacific are (i) a response to anthropogenic forcing and (ii) internal natural variability. Unfortunately, neither hypothesis is testable using high-end climate models (e.g., the CMIP5 models) due to large biases in their modern climate simulations. I will discuss two possible ways forward for testing these hypotheses.